Conventionally, in solid-state image pickup devices, electrons which are excited regardless of incident light may sometimes be a dark current and read out, due to crystal defect or metal contamination on the light receiving surface of a photodiode. This dark current causes white defects appearing in a picked-up image.
Thus, according to an applicable method, in a step of manufacturing the solid-state image pickup device, the dark current is reduced by storing positive holes through ion implantation into the part of the light-receiving surface of the photodiode, and rejoining electrons excited regardless of incident light and positive holes.
However, when there is an increased amount of positive holes stored in the light receiving surface part of the photodiode, it is difficult to read the photoelectrically-converted electrons from the photodiode. This results in a problem that some electrons without being read and remaining in the photodiode cause so-called afterimages.